Art and apparatus for indelible marking



July 5, 1932. R. s. BLAIR ART AND APPARATUS FOR I NDELIBLE MARKING FiledDec. 13, 1925 4 R O T N E v N T WER FIVE Patented July 5, 1932 PATENTOFFICE ROBERT S. BLAIR, OF STAMFORD, CONNECTICUT ART AND APPARATUS FORINDELIBLE MARKING Application filed December 13, 1928. Serial No.680,355.

This invention relatesto the art of, and apparatus for indelible markingand with regard to its more specific features to indelible Writing,printin or the like.

One of the objects b the invention is to provide a practical andeffective art whereby ma-rks incapable of removal or alteration may beapplied to an object. Another object is to provide a practical artwhereby in paper instruments, such as bank drafts, or

the like, may be dependably markedand protected a ainst alteration ofthe markin Another ob]ect is to provide apparatus efl1- cient in actionfor carrying on the above. art

in a convenient and practical manner. Other objects will be in partobvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction,combinations .of

several steps and relation and order of each of the same to one or moreof the others all as will be illustratively described herein,

and the scope of-the application of which will be indicated in thefollowifig claims.

In the accompanying drawing in whichare shown one-or more variouspossible embodiments of the several mechanical featermittent current isinduced by the primary tures of this invention;

Figure 1 is a diagrammatic representa-' detail certain parts detachedfrom Figure 3, I Figure 5 is adia'grammatic representation of anelectric circuit employed'in the apparatus of Figures 2, 3 and 4; and,

Figure 6 showsa fragment of material:

marked. with the above apparatus and parts of the apparatus. I i 46Similar reference characters refer to simelements, arrangements of partsand in the ilar parts throughout the several views of the drawing.

Referring now to the drawing in detail, in Figure 1 there is shown abase member 10 adapted to support a sheet of paper or similar materialadapted to be written upon or marked in an manner. This base member 10is prefera 1y grounded as at 10a and is formed of some suitable metal ofsuitable electrical conducting properties. Above the v base member 10 isshown a writing implement comprising an insulating shank or handle 11and a point 12. The,point 12 may be an ordinary steel pen-point securedto the handle 11in any desired manner. Connectm ed with the point 12 andextending 'up through the handle 11 is a conductor 13. A

coil'14 is connected through lead wires 15 and 16 with the conductor 13and the base member 10 respectively. Across the terminals of a battery17 are connected a coil 18 and a buzzer by means of the two conductors19 and 20. The buzzer comprising a core 21 anda spring retracted arm 22serves to make and break the battery 70 circuit, thereby causing anintermittent current to flow therethrough. The coils 14 and 18 are. ininductive relation and thus an in'- a orv battery circuit in thesecondary circuit -7 comprising the coil 14, the voltage being steppedup to the desired degree determined by the relative number of turns inthe two coils. It may here be noted that the term intermittent issomewhat broadly used to 0 include any current of intermittently effec-'tive value as, for example, an alternating current of sufficiently lowfrequency. The

secondary circuit, it will be seen, is through the coil 14,.lead wire15, conductor 13, point,

'12 to the base member 10 and thence back through the lead wire 16. r

The material to be marked such as a sheet of paper is placed upon thebase member 10,

the primary circuitis closed by means of the 99 switch 23 and thepen-point 12 is moved across the surface of the paper as ordinarily inwriting. The voltage intermittentl induced in the coil 14 causeselectric spar s to intermittently pass between the point 12 and the basemember 10 and through the paper interposed therebetween. The paper istherefore marked with the characters or figures drawn by the pen, thecharacters being burned thereinto by the intermittent sparks passingtherethrough. The effect is a multitude of spaced irregular perforationsor burns in the paper tracing the characters which are written with thepen. The irregularity of the resulting perforations where the sparkspass through the paper is of such nature that they cannot be covered upor erased. If desired, ink may be employed on the pen-point in the usualmanner in conjunction with the sparking. I

Referring now to Figures 2 and 3, there is shown an apparatus adaptedparticularly for marking paper instruments such as, for example, bankdrafts. There is provided a base member 24 having a rear upwardlyextending part 25 terminating in a pair of laterally extendingsupporting members 26. The members 26 form bearings for the trunnions 27of a rotatable cylindrical member 28 mounted therebetweeni The surfaceof the member 28 is provided with a plurality of longitudinal projectingsurfaces 29. Upon these surfaces 29 are raisedin relief the characterswhich are to be reproduced upon the paper; For example, upon one of thesurfaces 29, as shown in Figure 2, there may be raised the words Notover five dollars and the other surfaces 29 may be similarly marked forother words. A knurled handle 30 may be provided upon one of thetrunnions 27 for turning the member 28 to bring the desired surface 29to its lowermost position for marking with that surface. The entireapparatus thus far described is of metal and is grounded as shown inFigure 5 by means of a conductor 31.

Projecting upwardly from the base portion 24 are a pair of gui es 32upon which slides a supporting member 33. To the sup port 33 ispivotally connected, as at 34, one

end of a curved plate 35. This plate 35 is adapted to form a support forthe sheet of paper to be marked and is normally held in the positionshown in Figure 2 by means of a spring 36, its arched upper surfacebeing beneath the lowermost marking surface 29 of the member 28. Ahandle member 37 extending downwardly through the part 25 of the frameis connected at 38 to a lever 39 which is in'turn pivoted to the base 24as at plate 35 moves upwardly its left-hand end, as viewed in Figure 2,engages the lowermost surface of the part 28 first, whereupon the plate35 rocking about its pivot 34 the surface thereof in contact with themarking surface 29 is progressively moved to the right. In this mannerthe surface of the plate 35 is in contact with the part 29 substantiallyalong only a single transverse line at one time.

Referring now to Figure 4, there is shown in enlarged detail a portionof the member 28, a raised part 29 thereon, and the letters orcharacters 29a formed in relief upon the surface of the part 29.Inserted between the raised letters 29a of the member 29 and thesupporting plate 3'5 is shown a sheet of paper 42. As shown in thisfigure the plate 35 is formed of insulating material and inserted in itssurface are a plurality of parallel spaced longitudinal strips 43 ofconducting material, the strips being here shown as five in number.These strips 43 are insulated from each other by the material of themember 35, extend from one end thereof to the other end, as shown, andare positioned directly beneath the raised letters 29a when the latterare in posit-ion for marking. The surfaces of these strips 43 arepreferably substantially on a level with the surface of the insulatingsupport. As is diagrammatically shown in Figure 5, each of theconducting strips 43 is connected through a lead 44 with ,an individualcoil 45 and then ground as at 46. Each of these coils 45 is in inductiverelation with a coil 47 connected, for exanr ple, acrossthe terminals ofan alternating current generator 48. A voltage is therefore induced ineach of the coils 45 which tends to cause an alternating current to flowthrough each coil 45, the conductor 44 and strip 43 connected thereto,the raised letters 29a, the member 28, the conductor 31 and ground. Thusthere is an individual alternating current impressed between each strip43 and the surface of the part 29 opposite thereto when the strips 43are brought near enough to the surface 29a to permit the current to passtherebetween. The coils 45 are each so proportioned to the coil 47 thatthe voltage in the secondary circuits is stepped up to the requireddegree from that in the primary circuit. The-circuit from the generator48 through the primary coil 47 is controlled as diagrammaticallyindicated in Figure 5 by a switch 49. This switch 49 is preferablyassociated with the mechanism so that when the lever 37 is depressed toraise the supporting plate 35 the switch 49 automatically closes. Forexample, the contacts 49a and 49b of the switch 49 connectedrespectively with the conductors 50 and 51 on either side of the switchmay be positioned as indicated in Figure 3. As shown in this figure thecontact 49a is mounted upon the part Ill and insulated therefrom as byinsulation 52. The contact 49b is mounted upon a spring arm secured tothe lever 39 above its pivot and insulated therefrom as by insulation53. Thus when the lever 37 is depressed, the contact 495 swinging aboutthe pivot 40 engages the contact 49a and the circuit, through theprimary coil 47, is closed. The parts are preferably so proportionedthat this closing of the circuit occurs just before the supporting plate35 comes into marking position against the raised letters 29a.

The sheet of paper 42 to be marked having been placed upon the suporting plate 35, in this instance, in inverted position, with theportion thereof to be marked correctly positioned over the strips 43,and the cylinthe surface 29 the current will jump therethrough betweenthe adjacent portions of the surface 29 and the strips 43. As the plate35 is further raised by the handle 37 it rocks upon the marking surface29, the line ofcontact therebetween moving progressively to the right.As this action takes place electric current in the form of sparks passesbetween each of the respective strips 43 and the raised portion of thesurface 29 which is closest thereto at any instant. There being. asshown in Figure 4, five strips 43, it is possible for sparks to passthrough the paper at five spaced points at any one position of the plate35. It will be seen, however, that this will occur only when there is araised portion 29a of the surface 29 opposite the nearest part of theplate 35 which extends substantiall transversely 'of the st ips 43.

T e action of the appara us may be better understood by reference toFigure 6 wherein there is shown a portion of the surface 29 having theraised letters thereon, a portion of the supporting plate 35 with themetal strips 43 and a portion of the paper sheet 42 which has beenmarked. When the line of contact between the surface of the plate 35 andthe member 29 is along the bar marked a of the letter N, for example,sparks pass through the paper between each of the strips 43 and thisbar, resulting in a marking or perforation by burning the paper at thefive points as indicated at a. As the supporting plate 35 now rocks, theline 'of contact moves to the right and thus successive portions of theraised bar marked 6 are brought in sparking relation with the separatestrips 43 resulting in a row of spaced burns or perforations b on theaper. In this manner the paper is perftrated or burned by the sparks(passing therethrough at a plurality of space points which points tracethe outline of the raised letters or other characters upon the markingsurface 29. It is to be understood of course that a greater or lessernumber of the strips 43, with their individual coils, might be employed,but it is found that the number shown in the drawing producessatisfactory results.

.The alternating current causes the sparking through the paper at thespaced points to be intermittent, but if desired, direct current with abuzzer in the circuit may be employed as described with regard to theapparatus of Figure 1. It may be noted that the various parts of theapparatus are grounded so that there is no danger of the operator'receivini a shock. The perforations in the paper marking the passage ofthe sparks therethrough are irregular. in size and contour thusrendering erasure thereof in any manner impracticable. 'If desired, inkmay also be employed as in printing in conjunction with the sparks.

From the above, it will be seen that there are herein provided an artand apparatus for carrying on the art which attain the objects of theinvention and are well adapted to meet the requirements of practicaluse.

- As many possible embodiments may be made of the mechanical features ofthe above invention and as the art herein *described might be varied invarious parts all without departing from the scope of the invention, itis to be understood that all matter herein set forth or shown in theaccompanying drawing is to be interpreted as illustrative and not in alimiting sense.

I claim as my invention:

1. The herein described art which consists in formin legible charactersupon a medium adapted to receive them by mounting said medium inoperative relation to a conducting member and rocking over the oppositesurface of said medium a conducting member of predetermined form and ofa substantial potential difference with'respect to said first conductingmember.

2. The herein described art which consists in forming legible characters11 on amedium adapted to receive them by rocking over one surface ofsaid medium a plurality of members of predetermined form and impressingupon said members independent potentials such as to adapt each of themto spark through said medium at a plurality of relatively spaced points.

3. In apparatus of the class described, in combination, a deviceadaptedto support a sheet of paper and means associated with said deviceadapted to discharge electric sparks simultaneously at spaced pointsthrough said paper to mark the same, said means comprising independentsources of current whereby the discharge through certain of said pointsis not shunted by the dischar e through others.

%11 apparatus of the class described, in combination, a pair of spacedconducting members adapted to receive a sheet of paper therebetween, oneof said members being curved and elongated in the direction of itscurvature, means for passing an electric current between said twoconductors and of avoltage sufficient to pass through said papertherebetween to mark said paper, and means adapted simultaneously toroll said members relative to each other whereby the point of dischargethrough said paper is progressively changed along a predetermined line.

5. In apparatus of the class described, in combination, a device havinga marking surface formed of conducting material, a plurality ofconducting members opposite thereto, means for supporting a sheet ofpaper between said marking surface and said conducting members, andmeans for passing electric sparks between each of said conductors andsaid marking surface and through said paper therebetween.

6. In apparatus of the class described, in combination, a device havinga marking surface formed of conducting material of such predeterminedconformation as to form an intelligible character, a conductorpositioned opposite said surface, means for supporting a a sheet ofpaper between said surface and said conductor, and means for passingelectric sparks from spac'ed points on said marking surface to saidconductor and through said paper therebetween.

7. In apparatus of the class described. in combination, a device formedof conducting material and having characters raised in relief thereon,means for supporting a sheet of paper in operative relation thereto,means for passing an electric current throu h said paper at spacedpoints correspon ing to spaced points on said characters to mark saidpaper and trace said characters thereon, and means adapted to preventthe current passing fromcertain points to shunt current away fromothers.

8. In apparatus of the class described, in combination, a markingsurface formed of conductingmaterial, a. conducting member positionedopposite thereto, means for supporting a sheet of paper betweensaid-surface and said member, means for passing electric sparks betweensaid surface and said member and through said paper, and means forbringing different points of said surface successively into sparkingrelation with different points of said member.

9. In apparatus of the class described,

combination, a marking surface formed of conducting material, aplurality of strips of conducting material positioned 0p osite saidsurface and extending substantial y parallel thereto, means forsupporting a sheet of paper between said surface and said strips,

means for passing electric sparks between opposite points on saidsurface and said strips and through said paper, and means for bringingdifferent points of said surface successively into sparking relationwith said strips.

10. In apparatus of the class described, in combination, a pair ofspaced conducting members adapted to receive a sheet of papertherebetween, one of said members being inked, and having its surface inthe form of an intelligible symbol, means for bringing said sheet ofpaper between said two members into marking relation with said inkedmember, and means for passing on electric current between said twomembers and through said paper therebetween.

11. In apparatus of the class described, in combination, a markingsurface of a shape to form an intelligible character, means adapted tosupport a sheet of paper, means adapted to bring said marking surfaceand said sheet of paper into rolling contact, and means for passing anelectric current between said marking surface and said support throughsaid paper during said rolling contact.

12. In apparatus of the class described, in combination, a conductingmember, a plurality of conducting members opposite thereto, means forsupporting a sheet of paper between said first conducting member andsaid second conducting members, a separate source of electric currentconnected between said first conducting member'and each of said secondconducting members and means for moving saidfirst conducting member intosparking relation with said second conduct in g members.

13. In apparatus of the class described, in combination, a primarycircuit having a switch therein, a secondary circuit having a pair ofspaced terminals, means adapted to support a sheet of paper between saidterminals, means adapted to move said terminals toward each other withsaid paper therebe tween, and means actuated by said last means adaptedto control said switch one of said terminals having a vplurality ofrelatively spaced portions through which current is simultaneouslypassed. 7

14. The herein described art which consists in leading an electricpotential to two terminals one of which is curved, interposi'ng a mediumto be marked between said terminals, and relatively rolling saidterminals whereby the point at which the current passes through andmarks said medium is progressively changed thereon.

15. In apparatus of the class described, in combination, a contactmember, a second contact member of predetermined form, said v membercomprising a plurality of relatively insulated contact portions, meansadapted to bring said members substantially into en- I gagement with apiece of paper therebetween,

and means adapted to pass electric current through said relativelyinsulated parts to said first contact member, said current being of suchvoltage as to simultaneously spark from each of said parts through saidpaper.

In testimony whereof, I have signed my name to this specification this12th day of December, 1923.

' ROBERT S. BLAIR.

